VIRGINIA BEACH, Va. (WAVY) — More than 10,000 residents lost power Wednesday in Virginia Beach after a squirrel got into a substation, according to Dominion Energy. Although power was restored, the squirrel is not believed to have survived after getting into a substation and causing the outage.

While these bushy-tailed tree climbers are cute and relatively harmless, it’s not all that uncommon for them to cause electrical problems.

Entergy, a New Orleans-based energy company operating in the southern U.S., reported 15,000 of the 22,000 animal-related power outages in its Mississippi service area. The company said squirrels are its “undisputed” top animal offender, easily outpacing outages caused by raccoons (over 600 outages) and birds (1,200 outages).

Meanwhile, Unitil, a utility company serving over 107,000 in the northeast U.S., says squirrels cause an average of 8.5% of its outages each year. Unitil says since the animals use power lines for travel, it’s easy for them to inadvertently cause electrical trouble.

“When a squirrel climbs onto an electrical transformer, it may cross the bare wire that leads from the high-voltage line to the transformer,” Unitil said in a May blog. “If it were to simultaneously touch this wire and a part of the transformer with sufficient electrical ground, an electrical short can cause both a power outage and the electrocution of the animal.”

So even though squirrel outages may seem rare, at any given time, one or more of them may be wreaking havoc on a power line. Of the many places blacked out by squirrels are airports, a Veterans Affairs medical center and even the NASDAQ, the New York Times reports.

Outage-by-squirrel is more likely to happen in May, June and October, since Unitil says about 48% of all animal-related outages happen during these months.